This research investigates the pathways leading to the onset and participation in antisocial behaviors during early adolescence and seeks to identify the key regulators of such risk. Applying Sameroff and colleagues' developmental-transactional model, this project takes as its tasks: 1) the clarification of outcomes that are the focus of preventive efforts; 2) the identification of salient triggering marker behaviors along the identified development sequences; 3) identification of critical timing issues including age of initiation and temporal rate of progression from one marker behavior to the next; and 4) the elucidation of salient risk factors for developmental sequences. The findings have important implications for prediction and prevention of adolescent antisocial and delinquent behaviors. A sample of 500 5th and 7th grade males will be studied. This age group is focused on because of past findings implicating early adolescence as a critical time in the formation of antisocial behavior. These subjects, their families, and teachers will be surveyed four times over a five year period. At each survey point, the subjects will complete a self-report delinquency measure and other questionnaires dealing with several aspects of family functioning, peers and personal social networks, stress, and coping. In addition, multiple survey data will be obtained from parents and teachers, family interactions will be observed, official police and court records will be recorded, and scholastic functioning will be coded from school records. The focus of analyses is four-fold: 1) determining causes and effects of antisocial behavior; 2) testing prediction and effects of patterns of antisocial involvement; 3) evaluating dynamic interaction of change in behavior and psycho-social predictor status; and 4) evaluating predictors and effects of antisocial behavior. The interrelationship of parameters of antisocial behavior such as initiation age, progression rate, involvement level, chronicity, and official status will be studied. Analyses will also evaluate resiliency factors, differences in early and late initiations groups, and variations in predictor salience.